Hanna Instruments HI 8614N User Manual

Page 5

pH CALIBRATION WITH AUTOMATIC

TEMPERATURE COMPENSATION (HI 8614 family)

INITIAL PREPARATION

• Connect the pH electrode to the

BNC socket.

• Connect the temperature probe to

the transmitter.

Pour small quantities of pH 7.01 and pH 4.01 solution into two
clean beakers.

For accurate calibration use two beakers for each buffer solution, the
first one for rinsing the electrode, the second one for calibration. In
this way contamination of the buffers is minimized.
To get accurate readings, use pH 7.01 and pH 4.01 if you are going
to measure acid samples or pH 7.01 and pH 10.01 for alkaline
measurements.

Note: With HI 8614L the instruments

display can be used during
calibration without the need to
connect the ammeter and the
reading is directly expressed in
pH units.

The wire between the transmitter and the recorder/indicator/controller
should be a PVC insulated two wire with a wire diameter of at least
0.7 mm. This wire is fed through one of the smaller cable glands. The
maximum distance between the power supply and the amplifier is
300 m (1000'). It is not necessary to use shielded cable. The
transmitter is protected against inversion of supply voltage.

Electrode connection: connect the BNC
of the cable to the BNC socket on the
transmitter.

For HI 8614 family only: for automatic
temperature compensation, connect
the 2 terminals of the temperature probe
(

HI 76608, optional) to "TEMP. PROBE"

terminals.

If automatic temperature compensation
is not required, short the "TEMP. PROBE"
terminals with a resistance according to
the external temperature:

Temperature (°C)

Resistance (Ohms)

1634

1774

1922

2078

2242

2412

2590

A 2 kohm resistor is factory mounted for 25°C temperature compensation.

This manual is related to the following products:

HI 8615N